In the field of railroad transportation, different communication systems are known ensuring the transfer of computer data between a railroad vehicle and a motionless electronic station positioned along a railroad track, also called a railway track.
Wireless communication systems for example exist allowing electronic equipment onboard the railroad vehicle to communicate with an electronic station fixed to the ground. This communication is generally in accordance with standard IEEE 802.11.
Since the railroad vehicle is in motion, the communication system advantageously includes a plurality of electronic stations arranged along the railroad track, in order to provide continuous communication with the electronic equipment.
A control method is also known allowing the electronic equipment to adjust the transmission power of the data to the station based on the reception power of the data coming from that station. According to this control method, also known under the acronym TPC (Transmit Power Control), the transmission power level follows a complex control law so that the receiving power level is more or less homogenous from one piece of electronic equipment to another.
Such a control method allows the equipment to optimize its electricity consumption and, generally, to reduce the electromagnetic pollution in the environment. This method is primarily used in a static environment, in which the electronic equipment and the electronic station are substantially immobile. It is in particular used in communication systems according to standard IEEE 802.11.
However, such a control method is not suitable for use in a dynamic environment, for example when the electronic equipment is positioned in a moving railroad vehicle and communicates with an immobile electronic station positioned along a railroad track.
U.S. Pat. No. 7,577,415 to Richards et al. and U.S. Patent Publication Nos. 2005/0128970 of Tsien et al. and 2013/01710420 of Kobayashi are hereby incorporated by reference. No admission is made that these documents represent prior art to the present application.